Circular surgical staplers with isolating sleeves stored inside anvil

ABSTRACT

The present invention relates to surgical instruments and methods for enhancing properties of tissue repaired or joined by surgical staples and, more particularly to surgical instruments and methods designed to enhance the properties of repaired or adjoined tissue at a target surgical site, especially when sealing an anastomosis between adjacent intestinal sections so as to improve tissue viability, prevent tissue infection, and to prevent leakage. The present invention further relates to circular stapling instruments and elongated tubular hollow sleeves deployed from such stapling instruments and establishing an enclosure around the stapled and resected tissues at the anastomotic joint.

FIELD OF THE INVENTION

The present invention relates to surgical instruments and methods forenhancing properties of tissue repaired or joined by surgical staplesand, more particularly to surgical instruments and methods designed toreinforce and isolate the repaired or adjoined tissue at a targetsurgical site.

BACKGROUND OF THE INVENTION

Throughout the years the medical field has utilized various techniquesin an effort to join or bond body tissue together. Historically,suturing was the accepted technique for rejoining severed tissues andclosing wounds. Suturing is achieved with a surgical needle and asuturing thread, with the intended function of sutures to hold the edgesof a wound or tissue against one another during the healing process.Staples are used to replace suturing when joining or anastomosingvarious body structures, such as, for example, the bowel. The surgicalstapling devices employed to apply staples are generally designed tosimultaneously cut and seal an extended segment of tissue in a patient.

Linear or annular/circular surgical stapling devices are employed bysurgeons to sequentially or simultaneously apply one or more rows ofsurgical fasteners, e.g., staples, to body tissue for the purpose ofjoining segments of body tissue together and/or for the creation of ananastomosis. Linear surgical stapling devices generally include a pairof jaws or finger-like structures between which body tissue to be joinedis placed. When the surgical stapling device is actuated, firing barsmove longitudinally and contact staple drive members in one of the jaws,and surgical staples are pushed through the body tissue and into andagainst an anvil in the opposite jaw thereby crimping the staplesclosed. A knife blade may be provided to cut between the rows/lines ofstaples.

Annular or circular surgical stapling devices generally include anannular staple cartridge assembly including a plurality of annular rowsof staples (typically two or three), an anvil assembly operativelyassociated with the annular cartridge assembly, and an annular bladedisposed internal of the rows of staples. In general, an end-to-endanastomosis stapler typically places an array or group of staples intothe approximated sections of a patient's bowels or other tubular organs.The resulting anastomosis contains an inverted section of bowel whichcontains numerous “B” shaped staples to maintain a secure connectionbetween the approximated sections of bowel.

Anastomotic leaks may result in significant morbidity and frequentlydeath. In addition to the use of surgical staples, sealants, e.g.,synthetic or biological sealants, can be applied to the surgical site toguard against leakage. The biological sealants are typically applied tothe outer surface of the anastomosis in a separate step.

U.S. Pat. No. 7,776,081 entitled “Devices and methods for anastomosis”by Johan Zuidema et al. discloses a method of treating a human or animalorganism comprising inserting a tube formed from a biocompatible,biodegradable polymer into a lumen at a point of a desired anastomosis,joining two ends of biological vessels together to create ananastomosis, and with one end of the tube being firmly attached to aproximal end of the anastomosis, inverting the tube by drawing the otherend of the tube through the anastomosis and extending through theanastomosis such that the tube allows natural contents of the lumen todrain through and with the tube shielding the anastomosis in theorganism from the natural contents of the lumen.

An article entitled “The C-seal: A Biofragmentable Drain Protecting theStapled Colorectal Anastomosis from Leakage”, by A. N. Morks et al.,published in J. Vis. Exp. (45), p. 2223 (2010), discloses so calledC-seal which is a biofragmentable drain, which is stapled to theanastomosis with the circular stapler.

U.S. Patent Publication 2014/0358167 “ANASTOMOTIC SLEEVE DEVICE”discloses a system for performing a medical procedure comprising: a) astapler comprising: a detachable anvil head comprising an anvil surfaceand a hollow rod comprising a lumen protruding from the anvil surface, astapler shaft comprising a stapler surface and a spike protruding fromthe stapler surface, and a shape cutter, wherein the anvil surfacecomprises a groove, wherein the stapler surface comprises a staple portand a cutter port wherein the cutter can advance through the cutterport, and wherein the spike is proportioned to fit inside the lumen ofthe hollow rod; and b) a support structure comprising: a first shieldpiece comprising a first support surface and at least one first wallcomprising a first bottom edge wherein the first bottom edge is attachedto the first support surface and a second shield piece comprising asecond support surface, wherein the second shield piece is not attachedto the first shield piece, wherein the first support surface and/or thesecond support surface comprises a hole, and wherein the first supportsurface and the second support surface align with the anvil surface andthe stapler surface to provide for the delivery of a staple through thefirst support surface and the second support surface.

Various compression anastomotic ring systems have been pursued as areplacement to the staple-based anastomotic closure. For example, LARA™compression anastomotic ring system developed by novoGI™ utilizesnitinol-based compression ring specifically targeting low anteriorresection (LAR) procedures.

U.S. Pat. No. 7,527,185 “Compression anastomosis ring assembly andapplicator for use therewith” assigned to Niti Surgical Solutions Ltd.,discloses a compression anastomosis ring (CAR) assembly which comprises:a first portion which comprises: an anvil ring; and a second portionwhich comprises: a bottom ring positioned substantially parallel to andspaced apart from said anvil ring, said anvil ring and said bottom ringbeing adapted to be brought together in the presence of a closure forceapplied thereacross: at least one ring element, where one of said atleast one ring elements is a needle ring positioned on a side of saidbottom ring distal from said anvil ring, said needle ring having aplurality of needles extending generally transversely therefrom towardsaid first portion; and at least one spring element which provides arestorative force formed at least partially of a shape-memory alloy,said spring element positioned on one of said at least one ring elementsand being in compressive force transmissive contact with said bottomring, and wherein when said compression anastomosis ring (CAR) assemblyis positioned so as to hold between said anvil ring and said bottom ringtissue portions to be compressed and joined by anastomosis, said needlering is operative, in response to the closure force to drive saidplurality of needles through the tissue portions to be compressed and toanchor said plurality of needles in said anvil ring, and wherein whensaid anvil ring and said bottom ring are brought together in thepresence of the closure force holding the tissue portions therebetween,and when said anvil ring is anchored by said plurality of needles, therestorative force provided by said at least one spring element isoperative on said bottom ring to compress said tissue portions therebyeffecting anastomosis.

U.S. Pat. No. 5,250,058 “Absorbable anastomosic fastener means” assignedto ETHICON INC., discloses a mechanism which is capable of anastomosisof two lumens by an absorbable fastener. The fastener is made from twowasher-like plates. One such plate has holes to receive latching prongsprotruding from the other plate. Fastening is done through a singlelinear motion that causes the prongs to pierce the tissue, latches theprongs into a receiver and causes a knife blade to cut through excessfastener material and tissue. The ease of removal, by pulling themechanism through the formed anastomosis, is greatly enhanced. Thesystem can be used such that the plates can be placed in anyconfiguration to properly anastomose tissue. The patent discloses acompression anastomosis device comprising: a piercing ring containing aplurality of piercing flanges; a receiving ring containing a pluralityof receiving slots corresponding to said flanges; and spring meansplaced between said piercing and receiving rings to exert a spring forceon one of said piercing and receiving rings.

Post-operative leakage of the stapled tissue seals, includinganastomotic seals has been shown to lead to morbidity and mortality. Anumber of technologies are related to direct application of material tothe serosal layer after stapling by either dripping or spraying. Theproblems associated with these techniques are that access is verydifficult and visual assessment as to whether or not the material wasapplied to the right spot and completely around the anastomosis. Thematerial is also applied on top of the serosal layer when the targetsite is actually subserosal along the staple line. Applying atherapeutic agent to the serosal layer of the colon requires thematerial to migrate through the serosa and to the staple region, thenprovide a biological affect, and overcome the problems associated with aleak formation, all within 24-48 hours, assuming the material wasapplied to the correct spot intraoperatively. One of the mostchallenging steps in the application of a topical adjunctive therapy toa colorectal anastomosis is to provide the material to the site becauseof the extreme limitation in access to the site. Some colorectalanastomoses are performed relatively “low” in a patient (i.e. loweranterior resection) and the actual staple line is deep within the pelviccanal, which makes a topical application of material around thecircumference very difficult.

U.S. Pat. No. 8,511,533 “Annular adhesive structure” discloses asurgical stapling device for joining tissue portions, comprising: ahandle assembly; an anvil assembly at a distal end of the staplingdevice, the anvil assembly having a shaft for removably connecting theanvil assembly to the stapling device; a tubular body portion, thetubular body portion having a staple cartridge assembly containing aplurality of surgical staples in an annular array, the anvil assemblyand tubular body portion being juxtaposed with respect to one anotheralong the shaft and arranged so as to be approximated with respect toone another; and an applicator supported on the shaft of the anvilassembly, the applicator having a disc-shaped structure disposed betweenthe anvil member and tubular body portion, the disc-shaped structurehaving a channel radially oriented and open at lateral sides of thedisc-shaped structure, the channel being arranged for dispensing a woundtreatment material.

U.S. Pat. No. 8,372,094 “Seal element for anastomosis” discloses anassembly for disposing a seal element between tissue lumens comprising:a circular surgical stapling device comprising an anvil assembly and atubular body portion wherein the anvil assembly comprises an anvilmember and a first shaft and the tubular body portion comprises aplurality of surgical staples in a circular configuration and a secondshaft disposed inwardly of the surgical staples, the first shaft beingattachable to the second shaft; and a seal element disposable betweentissue lumens, the seal element comprising a first material and a secondmaterial wherein the first material promotes tissue ingrowth and thesecond material comprises a sealant.

U.S. Pat. No. 8,286,849 “Hub for positioning annular structure on asurgical device” discloses an assembly for disposing an annularstructure between adjacent intestinal sections, the assembly comprising:an annular surgical stapling device having an anvil assembly and atubular body portion, the anvil assembly having an anvil member and ananvil shaft, the tubular body portion carrying a plurality of surgicalstaples in an annular configuration, the tubular body portion having aconnection member disposed radially inward of the surgical staples, theanvil shaft of the anvil member including a flange and being attachableto the connection member of the tubular body portion; and a hub adaptedfor support on the anvil shaft to engage the flange of the anvil shaft,the hub selectively receiving the anvil shaft therein, and an annularstructure radially extending from the hub, the hub including a pluralityof resilient fingers extending substantially in a longitudinal directionand arranged to engage the flange of the anvil shaft to position theannular structure at a location spaced a distance from a tissuecontacting surface of the anvil assembly and the tubular body portion,wherein the annular structure comprises a material selected from thegroup consisting of: an adhesive, a sealant, a hemostat, and amedicament.

U.S. Pat. No. 8,257,391 “Annular support structures” discloses a systemfor joining a first body tissue and a second body tissue, the systemcomprising: a circular endoscopic stapling instrument having a staplecartridge assembly and an anvil assembly for approximating and joining afirst body tissue to a second body tissue, and an elongated shaftextending between the staple cartridge assembly and the anvil assembly;and a reinforcing support structure supported on the shaft of thestapling instrument at a location spaced a distance from the anvilassembly and spaced a distance from the staple cartridge assembly, thereinforcing support structure having a central hub for connection to theshaft of the stapling instrument and at least one annular reinforcingring supported on the central hub so that the at least one annularreinforcing ring is supported on the shaft at a location between thefirst body tissue and the second body tissue, wherein the at least oneannular reinforcing ring includes a radial outer ring and a radial innerring, the reinforcing support structure including at least one supportspoke integrally extending between the radial inner ring and the centralhub, and wherein, after firing of the stapling instrument, the at leastone annular reinforcing ring is interposed between and reinforces thejoined first body tissue and the second body tissue.

U.S. Pat. No. 8,167,895 “Anastomosis composite gasket” discloses amethod of forming an anastomosis between intestinal tissue sections,comprising the steps of: providing a circular surgical anastomosisdevice, the circular surgical anastomosis device including: an anvilassembly having an anvil member; and a tubular body portion having anannular knife operatively disposed therein and a shaft disposed radiallyinward of the annular knife, the anvil assembly being attached to theshaft of the tubular body; inserting the anvil assembly into a firstintestinal section; inserting the tubular body portion into a secondintestinal section; disposing a structure, including at least a firstring of a first material, a second ring of a second material, and athird ring between the first intestinal section and the secondintestinal section, the first ring comprising a disk having an apertureand the second ring comprising a disk having an aperture, the secondring having an outer perimeter, wherein the outer perimeter of thesecond ring is directly attached to the first ring and disposed withinthe aperture of the first ring, and the third ring radially extendingoutward from the first ring and beyond staple retaining slots of thetubular body portion, the structure possessing a wound treatmentmaterial consisting of at least one of an adhesive and a sealant; andfiring staples through the intestinal tissue sections and through thestructure.

U.S. Pat. No. 7,886,951 “Pouch used to deliver medication when ruptured”discloses an anvil assembly for a circular stapling device, the anvilassembly comprising: an anvil head configured to support an anvil platethereon; a shaft extending from the anvil head and configured toselectively engage a rod member of the circular stapling device; ananvil plate operatively connected to the anvil head, wherein the anvilplate includes an inner diametral edge, and wherein the anvil platedefines a plurality of staple forming pockets therein at a locationradially outward of the inner diametral edge; a recess formed in theanvil head, wherein the recess is defined by the inner diametral edge ofthe anvil plate and a rear surface of the anvil head; and a woundtreatment material disposed substantially within the recess.

U.S. Patent Publication No. 2012/0241492 “TISSUE THICKNESS COMPENSATORCOMPRISING AT LEAST ONE MEDICAMENT” discloses a stapling assembly foruse with a stapler, said stapling assembly comprising: an anvilcomprising a plurality of forming surfaces; a compensator attached tosaid anvil, wherein said compensator comprises a plurality of cavitiesaligned with said forming surfaces; and at least one medicamentpositioned within each said cavity.

U.S. Pat. No. 8,821,523 “Structure for applying sprayable woundtreatment material” discloses a guard for use in combination with ananastomotic surgical stapling apparatus, wherein the surgical staplingapparatus is configured and adapted to dispense staples from a staplepusher member of a body portion of the surgical stapling apparatus andto deliver wound treatment material from a stem of an anvil assembly ofthe surgical stapling apparatus to a target surgical site, wherein theguard comprises: a central hub defining a lumen therethrough forreceiving the stem of the anvil assembly of the surgical staplingapparatus; an annular cuff supported by the central hub and extending atleast substantially therearound, wherein the annular cuff is configuredto be disposed radially outward of a staple line of the surgicalstapling apparatus, and wherein the annular cuff defines an arcuateupper lip connected to an arcuate lower lip; and an annular flangeextending radially inwardly from a radially-outermost portion of theannular cuff, the annular flange being positioned for staples to befired therethrough.

U.S. Pat. No. 9,010,605 “Sliding sleeve for circular stapling instrumentreloads” discloses a surgical stapling device for joining tissueportions, comprising: a handle assembly; an elongate body extending fromthe handle assembly; a cartridge assembly supported on a distal end ofthe elongate body, the cartridge assembly including a staple cartridgecontaining a plurality of surgical staples in an annular array; an anvilassembly at a distal end of the surgical stapling device, the anvilassembly having a shaft for removably coupling the anvil assembly to thecartridge assembly and a head pivotally mounted to a distal end of theshaft, the anvil assembly translatable relative to the cartridgeassembly between a first position, where the anvil assembly is spacedfrom the cartridge assembly, and a second position, where the anvilassembly is approximated relative to the cartridge assembly for clampingtissue therebetween, the head of the anvil assembly transitionablebetween a first condition, where a tissue contacting surface of the headis substantially perpendicular to the shaft, and a second condition,where the tissue contacting surface of the head is tilted relative tothe shaft; and a sleeve member slidably disposed about the shaft of theanvil assembly, the sleeve member transitionable between a firstposition, where the sleeve member engages the head of the anvil assemblyto secure the head in the first condition, and a second position, wherethe sleeve member is disengaged from the head of the anvil assembly toallow the head to transition to the second condition.

There is a need to deliver medicants in the area of the anastomoticjoint for localized release to prevent ulceration and leaks, however itis difficult to create the necessary concentrations of medicants in anopen area. Further, there is a need to temporary isolate anastomoticjoint form the environment of the GI tract.

The known systems of isolating anastomotic joints can be complex,unreliable, and unable to fully isolate areas of resected and stapledtissue. The staple based anastomotic joining is a widely acceptedpractice but there is a need in improving the technology to preventpost-operative leakage of the stapled tissue seals to improve theviability of the tissue joined by staples.

SUMMARY OF THE INVENTION

The present invention relates to surgical instruments and methods forenhancing properties of tissue repaired or joined by surgical staplesand, more particularly to surgical instruments and methods designed toenhance the properties of repaired or adjoined tissue at a targetsurgical site, especially when sealing an anastomosis between adjacentintestinal sections so as to improve tissue viability, prevent tissueinfection, and to prevent leakage.

Tubular polymeric sleeves, optionally impregnated with a medicallyuseful agent, are carried on the anvil and/or on the stapling head andare stapled to the anastomotic joint as the anastomosis is performed.The sleeves are then left in the lumen after the stapling and removal ofthe circular stapler, creating an isolating enclosure around theanastomotic joint. The sleeves are optionally releasing medicants suchas antibiotic agents and/or microflora into the isolating enclosure thustreating the tissue in the areas proximal to the anastomotic joint,including stapled tissue, resected tissue, and surrounding tissue.

The present invention, in one aspect, relates to a circular surgicalstapler for anastomotic joining of tissue having an anvil having atissue facing end and an opposite distal end; the anvil having aperipheral staple bending zone and a coaxial circular knife recess onsaid tissue facing end; the anvil having a circumferential recess formedinside said anvil, with a circumferential entrance into saidcircumferential recess positioned on said tissue facing end coaxiallybetween the staple bending zone and the circular knife recess; acylindrical stapling head mounted on a support shaft, said stapling headcontaining a plurality of deployable staples in concentric arrays on atissue facing side and a concentric knife; a moveable shaft connectingthe anvil and stapling head; and an elongated hollow anvil sleeve havinga flange at a proximal end thereof, said anvil sleeve open at a distalend thereof and at the proximal end thereof; said flange positioned onthe tissue facing end of the anvil sleeve against said staple bendingzone; and said distal end of said anvil sleeve is releasably disposed insaid circumferential recess.

The present invention, in one aspect, relates to a method ofestablishing an anastomotic joint between tubular tissue lumens with thecircular stapling instrument, the method comprising the steps of:axially positioning the anvil sleeve on the anvil; axially insertingsaid anvil into a first tubular tissue and closing said first tubulartissue around said anvil; axially inserting said stapling head into asecond tubular tissue; connecting said anvil to said stapling head viathe moveable shaft; approximating said anvil and said stapling head tocompress said first and second tubular tissues between said staplinghead and said anvil; firing said anastomotic stapler to form a stapledanastomotic joint between said first and second tubular tissues andsimultaneously stapling said anvil sleeve to said first and secondtubular tissue; withdrawing said anastomotic stapler from said first andsecond tubular tissues, leaving said anvil sleeve inside said first andsecond tubular tissues, turning and inverting said anvil sleeveoutside-in; extending said anvil sleeve from said first tubular tissueinto said second tubular tissue; and leaving said anvil sleeve insidesaid first and second tubular tissues for sufficient time for at leastpartial healing of said tissues at the anastomotic joint.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a perspective view of a typical circular surgical staplinginstrument.

FIGS. 2A-2C show cross-sectional views taken from FIGS. 4, 5, 6 of U.S.Pat. No. 7,776,081 entitled “Devices and methods for anastomosis”.

FIG. 3 shows cross-sectional view taken from FIG. 6 of U.S. Pat. No.7,776,081 entitled “Devices and methods for anastomosis” with additionalarrow indicators.

FIGS. 4A-4F show schematic perspective and cross-sectional views ofanvil sleeves of the present invention.

FIGS. 5A-5D show schematic cross-sectional views of anvil sleeves of thepresent invention.

FIGS. 6A-6G show schematic perspective and cross-sectional views ofanvil sleeves of the present invention.

FIG. 7 shows schematic cross-sectional views of anvil known in the art.

FIGS. 8A-8F show schematic cross-sectional views of anvils of thepresent invention.

FIGS. 9A-9D show schematic cross-sectional views of anvil sleeves andanvils of the present invention.

FIGS. 10A, 10B and 11 show schematic cross-sectional view of stapler ofthe present invention in operation.

FIGS. 12 and 13 show schematic cross-sectional view of anvil sleeve ofthe present invention in operation.

DETAILED DESCRIPTION OF THE INVENTION

Surgery often involves joining of two or more layers of tissue togetherwith optional simultaneous sectioning of a portion of the tissue alongthe staple line. For example, colorectal surgery in many cases involvesthe resection of a segment of the colon and rectum. Following acolorectal resection, the colon and rectum are drawn together with acircular stapler and an end-to-end anastomosis is performed.Post-operative leakage of the anastomosis has been shown to lead tomorbidity and mortality.

Typical surgical stapling instruments have a staple-containing componentand an opposing anvil component, between which at least two tissuelayers to be joined are compressed prior to delivery of staples from thestaple-containing component, whereby staples are piercing both tissuelayers and are bent, deformed, or closed against the opposing anvilcomponent.

Referring now to FIG. 1, a generic surgical anastomosis staplinginstrument or stapling device for performing a circular anastomosisstapling operation is shown, with the figure taken from the U.S. Pat.No. 5,271,544 “Surgical anastomosis stapling instrument”, assigned toEthicon, Inc., Somerville, N.J., and incorporated herein by reference inits entirety for all purposes. Various modifications and iterations ofthe shown stapling device are known in the art, having similar features.The circular anastomosis surgical stapling instrument 500 includes adistal stapling head assembly 600 connected by a longitudinally curvedsupport shaft assembly 700 to a proximal actuator handle assembly 800.The stapling instrument includes an anvil assembly or anvil 1000 whichis slidable longitudinally relative to the stapling head assembly 600and mounted on an axially extending moveable shaft 1040. An optionalrotatable adjusting knob 820 is provided at the proximal end of theactuator handle assembly 800 for adjusting the spacing between thestapling head assembly 600 and the anvil assembly 1000. Otherapproximating means to compress adjacent sections of tissue are known toskilled artisans and can be used. An optional movable indicator 840 isvisible through an optional window 850 on top of the handle assembly 800to indicate the staple height and/or gap between the stapling headassembly 600 and anvil 1000 selected by rotation of the adjusting knob820. The indicator 840 is movable indicating that the anvil gap iswithin a desired operating range of the stapling instrument 500. Theposition of the indicator 840 also indicates whether the selected stapleheight is large or small.

A staple actuating lever 860 is pivotally mounted on the actuator handleassembly 800 for driving the surgical staples from the stapling headassembly 600 when the anvil assembly 1000 is closed to provide thedesired staple height. A pivotal latching member 880 is mounted on thehandle assembly 800 for locking the staple actuating lever 860 againstmovement to preclude actuation of the stapling head assembly 600 whenthe anvil gap is outside of a predetermined range. The stapling headassembly 600 includes a tubular casing 610 as well as a hollow tubularconnector 640 at the proximal end of the casing 610 which receives thedistal end of the support shaft 700. A ferrule or sleeve 720 overlapsthe joint between the tubular connector 640 and the distal end of thesupport shaft 700. The proximal end of the support shaft 700 is receivedby a tubular extension 740 at the distal end of the actuator handleassembly 800. A ferrule or sleeve 760 overlaps the joint between theproximal end of the support shaft 700 and the distal end of the tubularextension 740. The movable indicator 840 is visible through a window 850on top of the handle assembly 800 to indicate the staple height selectedby rotation of the adjusting knob 820.

Other versions and modifications of the circular surgical stapler areknown to a skilled artisan. There are typically at least two andfrequently more concentric stapling lines or concentric circular rows ofstaples-containing slots surrounding shaft 1040, with staples in eachrow typically staggered or offset relative to the staples in theadjacent row, to improve the sealing and prevent leakage along thestapling line.

Clinical evidence shows the formation of a full wall intestinal defectat or near the anastomotic site may occur as soon as 1-2 days post-op,with typical time period when the clinical symptoms of leaks occur beingfrom 1 to 5 days post-op. See, for example, K. Jönsson, H. Jiborn, B.Zederfeldt, “Breaking strength of small intestinal anastomoses”, TheAmerican Journal of Surgery, v. 145, pp. 800-803, 1983; Y.-H. Ho, M. A.T. Ashour, “Techniques for colorectal anastomosis”, World Journal ofGastroenterology, 16(13), pp. 1610-1621, 2010.

Referring now to FIGS. 2A-2C, tubular shaped colorectal drain of U.S.Pat. No. 7,776,081 is shown, whereby FIGS. 4, 5 and 6 of said patent arereproduced, showing the device stapled to the anastomotic joint.Referring now to FIG. 3, whereby FIG. 6 of said patent is againreproduced with added arrows indicating deficiencies of the device.Specifically, small dark arrows show areas that the device fails toisolate (specifically the stapled areas of tissue and cut areas oftissue) from the exposure to intestinal environment and/or microflora.Large white arrows schematically indicate that the device fails toprevent leakage if the anastomotic joint is transiently leaking.

Briefly, according to the present invention, an isolating sleeve orsleeves is/are positioned on the circular anastomotic stapler anddeployed with one end of the sleeve stapled to the anastomotic joint asthe staples from a circular anastomotic stapler are deployed and ananastomotic joint is established connecting two parts of a tissue lumen.As the circular anastomotic stapler is withdrawn, the sleeve or sleevesis/are released from the stapler and cover and isolate the areas oftubular tissue that were stapled together, providing additionalreinforcement and particularly isolating the just stapled and justresected areas from contaminations and potential infection. Optionally,a medicant is released from the sleeve into the pocket areas formedbetween the sleeve and the tissue, such medicant being for instance ananti-bacterial or anti-infective agent.

Referring now to FIGS. 4A-4F, showing embodiments of the presentinvention, FIG. 4A shows a schematic perspective view of generallyhollow, cylindrical shaped, flexible, and tubular anvil sleeve 200 ofthe present invention, with anvil sleeve 200 formed by wall 240connecting distal sleeve opening 220, formed by circular edge 210, toproximal flange 235 having proximal opening 230 formed in proximalflange 235.

Referring to FIG. 4B, a schematic cross-sectional view of anvil sleeve200 of FIG. 4A is shown. FIG. 4C shows a schematic cross-sectional viewof another embodiment of anvil sleeve 200 having a reinforcing buttress205 a installed onto flange 235 on the side opposite to tissue facingside of flange 235 which is side of flange 235 facing distal sleeveopening 220. Also shown is a distal portion 213 which a portion of wall240 which is distal to flange 235 and proximal to distal sleeve opening220. FIG. 4D shows a schematic cross-sectional view of anotherembodiment of anvil sleeve 200 having a similar reinforcing buttress 205b which is installed onto tissue facing side of flange 235, which isside of flange 235 not facing distal sleeve opening 220. Buttress 205 a,205 b can also prevent radial distention which can cause high tension ofthe tissue at the joint. Buttress can also help to spread coverage byanvil sleeve 200.

Turning now to FIG. 4E a schematic perspective view of anvil sleeve 200is shown with proximal opening 230 formed in proximal flange 235 beingsmaller than the diameter of wall 240 in the proximity to flange 235,thus forming inner flange 231 extending proximal flange 235 towardscenter of anvil sleeve 200 between wall 240 and proximal opening 230.FIG. 4F shows a schematic cross-sectional view of the embodiment of FIG.4E. Proximal opening 230 in the embodiments of FIGS. 4E-4F is configuredto accept moveable shaft 1040.

In some embodiments, at least a portion of anvil sleeve 200 has varyingmechanical properties, such as rigidity, flexibility, or thickness,along the sleeve. In one embodiment, flange 235 is thicker and lessflexible than the rest of anvil sleeve 200. In some embodiments anexpandable elastic ring is incorporated into circular edge 210.

Referring now to FIGS. 5A-5D, embodiments of anvil sleeve 200 are shownin a schematic cross-sectional view with a distal portion 213 of anvilsleeve 200 inverted and folded or rolled backwards onto wall 240. FIG.5A shows an embodiment of anvil sleeve 200 with distal portion 213inverted and folded flat twice on outside of wall 240. Distal portion213 can be folded once, twice (as shown), or more times. FIG. 5B showsan embodiment of anvil sleeve 200 with distal portion 213 inverted androlled on itself on the outside of wall 240 with a space of 3-15 mmbetween rolled distal portion 213 and flange 235. FIG. 5C shows anembodiment of anvil sleeve 200 with distal portion 213 inverted androlled on itself on the outside of wall 240 with a space of less than 3mm, such as 0, 1, 2, 2.5 mm between rolled distal portion 213 and flange235. FIG. 5D shows an embodiment of anvil sleeve 200 corresponding toembodiments of FIGS. 4E, 4F having inner flange 231 with distal portion213 inverted and rolled on itself on the outside of wall 240.

Turning now to FIG. 6A, a schematic perspective view of anotherembodiment of anvil sleeve 200 having a frustoconical shape withnarrower hollow portion at proximal flange 235 and wider hollow portionat distal sleeve opening 220 or at circular edge 210. FIG. 6B shows aschematic cross-sectional view of the embodiment of anvil sleeve 200shown in FIG. 6A. Also shown is a distal portion 213 which a portion ofwall 240 which is distal to flange 235 and proximal to distal sleeveopening 220.

Turning now to FIG. 6C, a schematic cross-sectional view of anembodiment of anvil sleeve 200 of the present invention is shown, withdistal portion 213 inverted and folded flat twice on outside of wall240. Distal portion 213 can be folded once, twice (as shown), or moretimes. FIG. 6D shows an embodiment of anvil sleeve 200 with distalportion 213 inverted and rolled on itself on the outside of wall 240with a space of 0-15 mm between rolled distal portion 213 and flange235.

Turning now to FIG. 6E, a schematic perspective view of an embodiment ofanvil sleeve 200 having a frustoconical shape with proximal opening 230formed in proximal flange 235 being smaller than the diameter of wall240 in the proximity to flange 235, thus forming inner flange 231extending proximal flange 235 between wall 240 and proximal opening 230.FIG. 6F shows a schematic cross-sectional view of the embodiment of FIG.6E. FIG. 6G, shows a schematic cross-sectional view of an embodiment ofanvil sleeve 200 of the present invention inner flange 231, with distalportion 213 inverted and folded flat twice on outside of wall 240.Proximal opening 230 in the embodiments of FIGS. 6E-6F is configured toaccept moveable shaft 1040.

Turning now to FIG. 7, a schematic cross-sectional view of anvil 1000 isshown as known in the art. Anvil 1000 is shown having distal end orupper portion 1003, sidewall 1002, tissue facing end or staples facingsurface 1001, staple bending zone 1025 at a periphery of staples facingsurface 1001 opposing staples 110 rows (not shown); moveable shaft 1040connected to anvil 1000, and circular or concentric knife abutting zoneor circular knife recess 1020.

Turning now to FIGS. 8A-8F, schematic cross-sectional views of anvil1000 of present invention are shown. FIG. 8A shows an embodiment ofanvil 1000 having an enclosed chamber or circumferential recess 1030 ainside, with circumferential entrance 1031 into circumferential recess1030 a. Circumferential entrance 1031 is positioned on tissue facing endor staples facing surface 1001. Circumferential entrance 1031 ispositioned coaxially around circular knife abutting zone or circularknife recess 1020; Circumferential entrance 1031 is in turn coaxiallysurrounded by staple bending zone 1025 located at the periphery ofstaples facing surface 1001. Circumferential entrance 1031 is configurednot to overlap with staple bending zone 1025 or with circular knifeabutting zone or circular knife recess 1020, with circular separationwall 1021 coaxially positioned between circumferential entrance 1031 andcircular knife recess 1020.

FIG. 8B shows an embodiment similar to one shown in FIG. 8A, but havingwider and expanded circumferential recess 1030 b inside anvil 1000, withthe same narrow circumferential entrance 1031 into circumferentialrecess 1030 a. The expansion of circumferential recess 1030 b insideanvil 1000 can be in any direction as shown, i.e. directed towards boththe periphery and center of anvil 1000.

FIG. 8C shows an embodiment similar to one shown in FIG. 8A, but havingwider and expanded circumferential recess 1030 c inside anvil 1000, withthe same narrow circumferential entrance 1031 into circumferentialrecess 1030 c. The expansion of circumferential recess 1030 c insideanvil 1000 can be in any direction but in this embodiment it is directedmostly towards center of anvil 1000.

FIG. 8F shows an embodiment similar to one shown in FIG. 8A, but havingwider and expanded circumferential recess 1030 d inside anvil 1000, withthe same narrow circumferential entrance 1031 into circumferentialrecess 1030 d. The expansion of circumferential recess 1030 d insideanvil 1000 can be in any direction but in this embodiment it is directedmostly towards periphery of anvil 1000.

FIG. 8E shows an embodiment similar to one shown in FIG. 8A, but havingcircumferential recess 1030 e without circular separation wall 1021between circumferential entrance 1031 and or circumferential recess 1030e and circular knife recess 1020.

FIG. 8D shows an embodiment similar to one shown in FIG. 8E, but havingcircumferential recess 1030 f merged with circular knife recess 1020.

Turning now to FIGS. 9A-9D, schematic cross-sectional views of anvil1000 of present invention are shown with anvil sleeve 200 installed.FIG. 9A shows an embodiment of anvil 1000 similar to the embodiment ofFIG. 8A with anvil sleeve 200 similar to the embodiments of FIG. 5A or6C installed. Flange 235 is abutting periphery of staples facing surface1001 and installed against staple bending zone 1025. The whole wall 240or at least a portion of wall 240 of anvil sleeve 200, such as distalportion 213, is inserted into and packaged into circumferential recess1030 a, being inserted through circumferential entrance 1031 and foldedon itself inside circumferential recess 1030 a.

FIG. 9B shows an embodiment of anvil 1000 similar to the embodiment ofFIG. 8B or 8D with anvil sleeve 200 similar to the embodiments of FIGS.5B-C or 6D installed. Flange 235 is abutting periphery of staples facingsurface 1001 and installed against staple bending zone 1025. The wholewall 240 or at least a portion of wall 240 of anvil sleeve 200, such asdistal portion 213, is inserted into and packaged into circumferentialrecess 1030 d, being inserted through circumferential entrance 1031 androlled on itself inside circumferential recess 1030 d.

FIG. 9B also shows an optional retaining ring 1011 installed insidecircumferential recess 1030 d. Retainer ring 1011 configured to looselyfit into circumferential recess 1030 d. Retainer ring 1011 can be madeof any material, such as metal, polymer, etc. Retainer ring 1011 can beelastic, rigid, or semi-rigid. As shown in FIG. 9B, distal portion 213can be optionally rolled around retainer ring 1011. Alternatively (notshown) distal portion 213 can be rolled on itself above retainer ring1011.

FIG. 9C shows an embodiment of anvil 1000 similar to the embodiment ofFIG. 8F with anvil sleeve 200 similar to the embodiments of FIG. 4B or6B installed. Flange 235 is abutting periphery of staples facing surface1001 and installed against staple bending zone 1025. The whole wall 240or at least a portion of wall 240 of anvil sleeve 200, such as distalportion 213, is inserted into and packaged into circumferential recess1030 f, while positioned to avoid any interference with circular knifemoving against and within circular knife recess 1020.

FIG. 9D shows an embodiment of anvil 1000 and anvil sleeve 200 similarto the embodiment of 9B, but with anvil sleeve 200 having inner flange231.

According to the embodiments of the present invention, in allembodiments, anvil sleeves 200 as shown in FIGS. 4, 5, 6 are installedonto anvils 1000 as shown in FIG. 8, with flange 235 abutting peripheryof staples facing surface 1001 and opposing staples 110 rows andinstalled against staple bending zone 1025. The whole wall 240 or atleast a portion of wall 240 of anvil sleeve 200, such as distal portion213, is inserted into and packaged into circumferential recess 1030,optionally inserted through circumferential entrance 1031 and optionallyfolded on itself or rolled on itself inside circumferential recess 1030.In all embodiments, excluding embodiments having inner flange 231, anvilsleeves 200 are configured and positioned to avoid any interference withcircular or concentric knife moving against and within circular kniferecess 1020. In embodiments having inner flange 231, inner flange 231 iscut by the action of concentric knife during stapling.

According to one embodiment of the present invention, a first portion ofanvil sleeve 200, comprising flange 235 is mounted onto staple bendingzone 1025; a second portion of anvil sleeve 200 comprising distalportion 213, is releasably stored in circumferential recess 1030; and athird portion of anvil sleeve 200 comprising a part of wall 240intermediate between flange 235 and distal portion 213 passes throughcircumferential entrance 1031.

As shown above, anvil sleeve 200, which can be made of polymeric,flexible, and at least partially elastic materials, is configured tohave at least a portion of wall 240 to releasably fit inside anvil 1000with anvil 1000 at least partially enveloping anvil sleeve 200 wall 240inside circumferential recess 1030.

In one embodiment, walls 240 of anvil sleeve 200 contain multipleapertures, pores or perforations (not shown), having size from about 0.1mm to about 3 mm, such as 0.25 mm, 0.5 mm, 1 mm. In one embodiment, onlydistal portion 213 has multiple apertures, pores or perforations (notshown). In one embodiment, apertures are round, square, triangular, orsimilar. In another embodiment the apertures comprise elongated cutswith length to width ratio from 5 to 150, such as for width of the cut0.1 mm, the length of the cut being 10 mm.

Referring now to FIG. 10A, a schematic cross-sectional partial view of aportion of circular stapler performing anastomotic joining of tubulartissues T1 and T2 is presented. Anvil 1000 is shown disposed withintubular tissue T1 and connected to stapling head 600 via moveable shaft1040. Stapling head 600 is shown disposed within tubular tissue T2 andsupported on support shaft assembly 700. For simplification, themechanism of staples deployment and mechanism of deploying tissuecutting circular or concentric knife 601 are not shown. FIG. 10 showsanvil 1000 and stapling head 600 approximated, compressing tissue T1 andT2 between them. Flange 235 of anvil sleeve 200 is disposed betweenstapling head 600 and anvil 1000, with flange 235 on tissue facing sideof anvil sleeve 200.

FIG. 10 shows embodiment of anvil sleeve 200 of FIGS. 5B, 5C, 6D,mounted on embodiment of anvil 1000 similar to embodiment of FIG. 8C.Any other embodiments of anvil sleeve 200 and anvil 1000 of the presentinvention can be substituted for embodiments shown in FIG. 10 and infra.

Referring now to FIG. 10B, an embodiment of the present inventionsimilar to one shown in FIG. 10A is presented, but with anvil sleeve 200having inner flange 231. During stapling, inner flange 231 is cut by theaction of concentric knife 601.

Referring now to FIG. 11, the configuration of embodiment of FIG. 10 isshown after actuating stapling instrument 500, i.e. after staples 110fired thus establishing a stapled joint between tissues T1 and T2 withstaples 110 concentrically arranged in one or more concentric rowsaround tissue donut or cut-out 120 which is formed by deploying and thenretracting tissue cutting circular or concentric knife 601. Areas 202 ofanvil sleeve 200 which are opposing staples 110 rows and correspondingto flange 235, are stapled to tissues T1 and T2.

After deploying staples 110 and cutting out tissue cutout 120 thusestablishing the anastomotic joint, with anvil sleeve 200 stapled totissues T1 and T2, in the area corresponding to flange 235, circularstapler 500 is withdrawn in the direction of arrow A. As anvil 1000moves past staples 110 in the direction of arrow A, with anvil sleeveproximal end or flange 235 immobilized on tissue by staples 110, anvilsleeve 200 is turned outside-in and inverted with distal portion 213released from circumferential recess 1030.

For embodiments of anvil sleeve 200 having inner flange 231, as wasshown in FIG. 10B, during stapling, inner flange 231 is cut from anvilsleeve 200 by the action of concentric knife 601. Inner flange 231 isthus separated from anvil sleeve 200 and remains between anvil 1000 andstapling head 600 even after removal of circular stapler 500 formtubular tissues T1 and T2.

Referring now to FIG. 12, a schematic cross-sectional view ofconfiguration shown in FIG. 11 is presented, omitting circular stapler500. Arrow B shows the direction where anvil sleeve 200 distal end ispulled by anvil 1000 (not shown). Anvil sleeve 200 thus is turnedoutside-in and inverted while released into tubular tissue T2 fromcircumferential recess 1030.

Referring now to FIG. 13, a schematic cross-sectional view ofconfiguration after removal of circular stapler 500 and deployment ofanvil sleeve 200 around and onto anastomotically joined tissue lumens T1and T2 is shown. Anvil sleeve 200 is stapled to tissues T1 and T2 withintissue lumen T1 and then inverted/turned outside-in, passes over area oftissues T1 and T2 stapled by staples 110, extending from tissue lumen T1into tissue lumen T2, and then completes covering the areas of cut andstapled tissues T1 and T2.

Advantageously, areas of cut and stapled tissues T1 and T2 arebeneficially protected by anvil sleeve 200 which extends above and belowthe immediate vicinity of the established anastomotic joint, enablingisolation and protection of vulnerable tissues around the anastomoticjoint, which can be subject to ulceration and leaks.

According to one embodiment of the present invention, the sequence ofusing anvil sleeve 200 of the present invention while establishing ananastomotic joint and isolating and protecting the anastomotic joint isas follows:

-   a) Axially positioning anvil sleeve 200 on anvil 1000 with flange    235 abutting periphery of staples facing surface 1001 and installed    against staple bending zone 1025, with at least a portion of wall    240 of anvil sleeve 200 inserted into and packaged into    circumferential recess 1030;-   b) Axially inserting anvil 1000 into tubular tissue T1 and closing    tissue T1 around anvil 1000;-   c) Axially inserting stapling head 600 into tubular tissue T2;-   d) Connecting anvil 1000 to stapling head 600 via anvil shaft 1040;-   e) Approximating anvil 1000 and stapling head 600 and compressing    tubular tissues T1 and T2 between stapling head 600 and anvil 1000;-   f) Firing anastomotic stapler 500 and establishing stapled    anastomotic joint between tissues T1 and T2 and simultaneously    stapling anvil sleeve 200 to tissues T1 and T2 in the area of flange    235;-   g) Withdrawing anastomotic stapler 500 from tissue lumens T1 and T2    and leaving anvil sleeve 200 inside tissue lumens T1 and T2, while    anvil sleeve 200 is released from circumferential recess 1030,    turned outside-in and inverted and deployed inside tissue T2;-   h) Allowing anvil sleeve 200 to extend from its proximal end and    flange 235 stapled to tissue T1 over the resected/stapled areas of    tissues T1 and T2 and into tissue lumen T2 where the opposite distal    end of anvil sleeve 200 is then positioned; and-   i) Leaving anvil sleeve 200 inside tissue lumens T1 and T2 until at    least partial healing of tissues at the established anastomotic    joint.

Complete steps of anastomotic surgical procedures, e.g. application ofpurse string sutures are not listed above, but will be known to skilledartisans. Additional steps after the installation of anvil sleeve 200include:

-   j) Optionally releasing medicants accelerating healing and/or    preventing infection and/or managing inflammation from anvil sleeve    200;-   k) Optionally releasing a specialized microflora from anvil sleeve    200; and-   l) Allowing the anvil sleeve 200 to pass through the GI tract out of    the body after a period of from 3 days to about 8 weeks, more    preferably 1 week, 2 weeks, 3 weeks, 4 weeks, or 6 weeks.

In certain embodiments anvil sleeve 200 is made of non-resorbablepolymers or composites, preferably from polymeric and elastomericmaterials. In one embodiment, sleeves are made of materials with lowelasticity, low elastomeric properties materials, or are made ofelastomeric compressible/expandable materials, and are made of at leastpartially resorbable or erodible/soluble materials. Sleeves 200 areexcreted as the stapled areas of tissues T1 and T2 eventually undergonecrotic transformation and die off.

In certain embodiments anvil sleeve 200 is made of at least partiallyresorbable or erodible/soluble materials which are known to a skilledartisan, with time to at least partially dissolve or resorb from about 3days to about 30 days in the gastro-intestinal (GI) tract, such as 1week, 2 weeks, 3 weeks, or 4 weeks, most preferably 2-4 weeks. In someembodiments, sleeves 200 walls 240 are made from non-resorbable polymersor composites.

According to the present invention, in addition to shielding/isolatingthe areas of resected and stapled tissue from GI environments, there isprovided an optional release of medicants accelerating healing and/orpreventing infection from anvil sleeve 200. Further, a specializedmicroflora can be released from anvil sleeve 200.

According to the present invention, anvil sleeve 200 is optionally atleast partially coated or impregnated with releasable antimicrobialagents. All portions of anvil sleeve 200 can be treated with suchagents, or specific portions which are in contact with areas of tissuesT1 and T2 or specific portions which are not in contact with areas oftissues T1 and T2 can be coated or impregnated with releasable medicallyuseful agents, such as antimicrobial agents. Advantageously, anvilsleeve 200 shields or isolates areas of stapled and cut tissue from theGI environment and enables establishment of higher sustainedconcentration of anti-microbial agents or other medicants, such asspecific microflora, in the immediate vicinity of these areas of tissue.Such treatment is thought to minimize formation of tissue ulcerationsand other defects and decrease the occurrence of anastomotic leaks.

Alternatively, or in addition to the above, agents that reduce/manageinflammation can be coated onto and/or impregnated into the sleeve.

Thickness of sleeves 200 walls 240, is from about 20 microns to about 2mm, more preferably from 50 microns to 1 mm, such as 50, 100, 200, 300,500 microns.

The length of anvil sleeve 200 is configured to enable sleeve 200 to beturned outside-in and extend from stapled areas of tissue T1 to belowstapled area of tissue T2, but still remain fully within GI tract. Insome embodiments, the length of sleeve 200 is from about 5 mm to about75 mm, more preferably 10 mm to 50 mm, such as 10, 15, 20, 25, 30, 40,50 mm.

In some embodiments there are apertures or micro-apertures (not shown)formed in anvil sleeve 200.

While the invention has been described above with reference to specificembodiments thereof, it is apparent that many changes, modifications,and variations can be made without departing from the inventive conceptdisclosed herein. Accordingly, it is intended to embrace all suchchanges, modifications, and variations that fall within the spirit andbroad scope of the appended claims.

What is claimed is:
 1. A circular stapling instrument comprising: a) ananvil having a tissue facing end and an opposite distal end; the anvilhaving a peripheral staple bending zone and a coaxial circular kniferecess on said tissue facing end; the anvil having a circumferentialrecess formed inside said anvil, with a circumferential entrance intosaid circumferential recess positioned on said tissue facing endcoaxially between the staple bending zone and the circular knife recess;b) a cylindrical stapling head mounted on a support shaft, said staplinghead containing a concentric knife and a plurality of deployable staplesin concentric arrays on a tissue facing side of said stapling head; c) amoveable shaft connecting the anvil and stapling head; and d) anelongated hollow anvil sleeve having a flange at a proximal end thereof,said anvil sleeve open at a distal end thereof and at the proximal endthereof; said flange positioned on the tissue facing end of the anvilagainst said staple bending zone; wherein said distal end of said anvilsleeve is releasably disposed in said circumferential recess, wherein acircular separation wall is formed on said tissue facing end of saidanvil coaxially between the circumferential entrance and the circularknife recess.
 2. The circular stapling instrument of claim 1, whereinthe circumferential entrance is configured not to overlap with thestaple bending zone.
 3. The circular stapling instrument of claim 1,wherein the circumferential entrance is configured not to overlap withthe circular knife recess.
 4. The circular stapling instrument of claim1, wherein said anvil sleeve is tubular or frustoconical.
 5. Thecircular stapling instrument of claim 1, wherein said anvil sleeve, saidcircumferential recess, and said circumferential entrance are configuredto avoid any interference and any contact of the anvil sleeve with theconcentric knife moving against and within circular knife recess.
 6. Thecircular stapling instrument of claim 1, wherein said anvil sleeve, saidcircumferential recess, and said circumferential entrance are configuredto avoid any interference and any contact of the anvil sleeve with theconcentric knife before, during, and after stapling with said circularstapling instrument.
 7. The circular stapling instrument of claim 1,wherein said anvil sleeve further comprises an inner flange extendingthe flange towards center of said anvil sleeve.
 8. The circular staplinginstrument of claim 7, wherein said inner flange is cut by saidconcentric knife during stapling with said circular stapling instrument.9. The circular stapling instrument of claim 1, wherein a portion of theanvil sleeve intermediate between the flange and the distal end of saidanvil sleeve passes through the circumferential entrance.
 10. Thecircular stapling instrument of claim 1, wherein said anvil sleeve isfolded on itself or rolled on itself or inverted or turned outside-in orturned inside-out at said distal end of said anvil sleeve.
 11. Thecircular stapling instrument of claim 1, wherein said anvil sleevefurther comprises a buttress disposed on the flange.
 12. The circularstapling instrument of claim 1, wherein said anvil sleeve has multipleperforations.
 13. The circular stapling instrument of claim 1, whereinsaid anvil sleeve has multiple perforations in the distal end thereof.14. The circular stapling instrument of claim 1, wherein at least aportion of said anvil sleeve is erodible, dissolvable, or resorbable ina mammalian gastrointestinal tract over a period ranging from 1 to 8weeks.
 15. The circular stapling instrument of claim 1, wherein saidanvil sleeve is at least partially coated or impregnated with areleasable anti-bacterial, anti-microbial, anti-infective agent,bacterial culture, or combinations thereof.
 16. The circular staplinginstrument of claim 1, wherein at least a portion of said anvil sleevehas varying mechanical properties along the sleeve.
 17. The circularstapling instrument of claim 1, wherein the flange is thicker and lessflexible than the rest of said sleeve.
 18. The circular staplinginstrument of claim 1, wherein an expandable elastic ring isincorporated into said distal end of said anvil sleeve.
 19. A method ofestablishing an anastomotic joint between tubular tissue lumens with thecircular stapling instrument of claim 1, the method comprising the stepsof: a. axially positioning the anvil sleeve on the anvil; axiallyinserting said anvil into a first tubular tissue and closing said firsttubular tissue around said anvil; b. axially inserting said staplinghead into a second tubular tissue; c. connecting said anvil to saidstapling head via the moveable shaft; d. approximating said anvil andsaid stapling head to compress said first and second tubular tissuesbetween said stapling head and said anvil; e. firing said anastomoticstapler to form a stapled anastomotic joint between said first andsecond tubular tissues and simultaneously stapling said anvil sleeve tosaid first and second tubular tissue; f. withdrawing said anastomoticstapler from said first and second tubular tissues, leaving said anvilsleeve inside said first and second tubular tissues, g. turning andinverting said anvil sleeve outside-in; h. extending said anvil sleevefrom said first tubular tissue into said second tubular tissue; and i.leaving said anvil sleeve inside said first and second tubular tissuesfor sufficient time for at least partial healing of said tissues at theanastomotic joint.